Authors: Cavaca, Lídia A. S.; Rodrigues, Catarina A. B.; Simeonov, Svilen P.; Gomes, Rafael F. A.; Coelho, Jaime A. S.; Romanelli, Gustavo Pablo; Sathicq, Angel Gabriel; Martínez, José J.; Afonso, Carlos A. M.
Publication Date: 2018.
Language: English.
Abstract:
The acid-promoted methanolysis of oleuropein was studied using a variety of homogeneous and heterogeneous acid catalysts. Exclusive cleavage of the acetal bond between the glucoside and the monoterpene subunits or further hydrolysis of the hydroxytyrosol ester and subsequent intramolecular rearrangement were observed upon identification of the most efficient catalyst and experimental conditions. Furthermore, selected conditions were tested using oleuropein under continuous flow and using a crude mixture extracted from olive leaves under batch. Formation of (−)-methyl elenolate was also observed in this study, which is a reported precursor for the synthesis of the antihypertensive drug (−)-ajmalicine.
Author affiliation: Cavaca, Lídia A. S.. Universidade de Lisboa; Portugal
Author affiliation: Rodrigues, Catarina A. B.. Universidade de Lisboa; Portugal
Author affiliation: Simeonov, Svilen P.. Universidade de Lisboa; Portugal. Bulgarian Academy of Science; Bulgaria
Author affiliation: Gomes, Rafael F. A.. Universidade de Lisboa; Portugal
Author affiliation: Coelho, Jaime A. S.. Universidade de Lisboa; Portugal
Author affiliation: Romanelli, Gustavo Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas "Dr. Jorge J. Ronco". Universidad Nacional de la Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Ciencias Aplicadas; Argentina
Author affiliation: Sathicq, Angel Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas "Dr. Jorge J. Ronco". Universidad Nacional de la Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Ciencias Aplicadas; Argentina
Author affiliation: Martínez, José J.. Universidad Pedagógica y Tecnológica de Colombia; Colombia
Author affiliation: Afonso, Carlos A. M.. Universidad Pedagógica y Tecnológica de Colombia; Colombia
Repository: CONICET Digital (CONICET). Consejo Nacional de Investigaciones Científicas y Técnicas
Authors: Sanchez, Laura Mabel; Sathicq, Angel Gabriel; Baronetti, Graciela Teresita; Thomas, Horacio Jorge
Publication Date: 2014.
Language: English.
Abstract:
Dawson-type heteropolyoxometalate compounds (HPC) P2M18O62-6 (M= Mo, W) have received increasing attention in the catalytic field due to the combination of redox and acidic properties in the same structure. It has been proved that the introduction of vanadium into the Keggin framework is beneficial for redox Catalysis, shifting its activity from acid to redox-dominated. In this work we prepared and characterized vanadium (V) substituted Wells-Dawson heteropolysalt (WDKV). Fresh solid samples were characterized by 31P MAS-NMR, FTIR, SEM, XRD, TGA and Potentiometric titration measurements. Also, we performed the oxidation of a 1,4-dihydropyridine using WDKV as catalyst in acetonitrile media, with H2O2 as oxidant agent. The optimal procedure is the following: 1 mmol% of WDKV, a ratio 1,4-DHP: H2O2 (1:214) at reflux of acetonitrile. It must be noted that along all reactions, no secondary products were observed.
Author affiliation: Sanchez, Laura Mabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas ; Argentina
Author affiliation: Sathicq, Angel Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas ; Argentina
Author affiliation: Baronetti, Graciela Teresita. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Ingeniería Química. Laboratorio de Procesos Cataliticos; Argentina
Author affiliation: Thomas, Horacio Jorge. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas ; Argentina
Repository: CONICET Digital (CONICET). Consejo Nacional de Investigaciones Científicas y Técnicas